One person in every 500 has Parkinson's and around 127,000 people are living with the condition in the UK. The aim of the study is to identify new genes that predispose or cause Parkinson's Disease or Parkinsonism. There is a pressing need to study the genetic makeup of family members both with and without Parkinson's. As families share a common genetic background, it is easier to find new Parkinson's genes by studying the genetic makeup of people with Parkinson's alongside other members of their families. We are particularly interested in studying the genetic makeup of two groups of people: